


Don't Run

by WinterTheWriter



Series: Building Happily Ever After [19]
Category: Captain America (Movies), Doctor Who, Doctor Who (2005), The Avengers (Marvel Movies), The Avengers (Marvel) - All Media Types
Genre: (sort of), Angst, Cliffhanger, Cool motive still murder, Dissociative Identity Disorder, Drama, M/M, Self-Harm
Language: English
Status: Completed
Published: 2017-02-21
Updated: 2017-02-21
Packaged: 2018-09-26 03:30:21
Rating: Explicit
Warnings: Graphic Depictions Of Violence, No Archive Warnings Apply
Chapters: 2
Words: 2,318
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9860309
Author URL: https://archiveofourown.org/users/WinterTheWriter/pseuds/WinterTheWriter
Summary: Steve wakes up to a surprise he really wishes he wasn't expecting.





	1. Chapter 1

**Author's Note:**

> Okay, so, first and foremost: I tagged DID because it is the closest equivalent to what Koschei/the Master are, but it is NOT completely accurate. I've taken artistic liberty since they ARE aliens, and their versions of mental illnesses would be, reasonably, different. This is NOT an accurate depiction of what actual, real life DID is like, and it is not intended to be taken that way. The Master is literally a separate person from Koschei, born within his own mind and sharing the same body and fighting for control. He is NOT just a headmate -- think of him more like a really, really conjoined twin who happened to be born a while later thanks to Rassilon. I'm not pulling a Split, I promise (also fuck that movie).
> 
> Second, yay update!! I'm home sick today so I figured I'd try to get this out, even though it's only the first part. Thank you all for being so patient with me -- I literally don't have weekends or days off right now, so even when I DO get free time, I pretty much just use it to mindlessly watch TV/sleep/cry/etc.
> 
> Third, the Master is very creepy and there's a warning here for, like, .2 seconds of touching Steve's chest without consent but that's as bad as it gets. There's never going to be explicit assault like that in my stories.
> 
> Fourth, ENJOY!

“Koschei? You alright in there?” Steve’s worried voice carries through the closed bathroom door, but it falls on deaf ears. After a beat, Steve tries again. “You’ve been in there an awful long time. I hear the shower’s still on but there can’t be any hot water by now…,” he trails off. 

Silence. 

“Um. I’m gonna use my privilege as your boyfriend to just…,” Lapsing into silence, Steve pushes open the bathroom door and peeks in, still bleary-eyed from sleep. Koschei’s standing under the spray of the shower, back turned to Steve as he faces the wall, still as a statue, still as a corpse. “Sweetheart?” Steve hedges carefully, walking in fully. The shower-curtains are pushed to the far side of the stall, dry and unused, and the bathroom floor shines wetly and squelches coldly under Steve’s bare footsteps. With a hesitant, slow hand, Steve reaches out and gently rests a hand on Koschei’s shoulder. 

Immediately, Koschei’s body begins to shake, and Steve opens his mouth to comfort him before he hears the low, sinister grumble of laughter that most certainly does /not/ belong to the man he loves. It’s with a sinking, bone-chilling feeling that Steve realizes what must’ve happened. Still, he keeps his hand where it is. It’ll be a cold day in hell when Steve abandons him. 

“Master?” 

“Ooooh, good boy.” The Master turns around sharply and sends Steve stumbling back a couple steps. There’s an unnaturally large grin spread across the Master’s face, brows furrowed and his eyes dark, but with a glimmer of madness and /rage/ in them that’s enough to really and properly knock him off guard. “You figured it out /all by yourself!/ My, he did pick a clever ape, didn’t he?” 

“He…,” Steve starts, floundering. The Master rolls his eyes and his whole head with it, shutting off the shower and stepping out with this predatory grace Koschei’s only ever had an echo of in battle, and even then it was the movements of a soldier. For the first time, Steve really, truly understands just how separate the two are. This is no mental illness, not like D.I.D on Earth at least. This is an intruder. Steve knows it, really knows it, but he does not run.

“/Koschei./ Our Koschei. Our sweet litt—,”

“He’s not yours,” he interrupts, firmly as he finally finds his bravado, straightening up and hardening his gaze. “You need to leave.”

“Possessive, are we? Adorable.” The Master gives him an exaggerated pout and saunters forward, naked hips swinging in a way that would usually drive him crazy. Now, being controlled by this…this /monster/, Steve feels nothing but disgust. A cold, pruned finger trails down Steve’s chest as the Master looks at him through his lashes, batting them playfully, and Steve meets his eyes, face like stone, and pushes the finger away. 

“Don’t touch me.” 

“Why not? We’re the same person, after all~,” he taunts, licking his lips lewdly. Steve suddenly wishes he were in his suit, not a t-shirt and pajama pants. Steve does not run.

“You are /not/ the same person,” Steve grits out, squaring his shoulders and automatically falling into parade’s rest. “You are not my Koschei. You are a parasitic psychopath created by /mistake/, so desperate for attention that you willfully take over the mind of an innocent man just to throw yourself at his boyfriend. You’re /pathetic/.” 

The Master’s eyes narrow dangerously, his smile turning sinister and /wrong/ and, with just a twitch of his fingers, blue electricity starts to crackle and buzz as it winds around his hand in lightening-fast bolts like glowing vines. “Hasn’t anyone taught you to respect your elders, /human/?” He hisses out the word like a curse, face twisting into a grimace around the letters as if he spat it onto Steve’s foot. Steve takes a half-step back but he does not run. 

“I never agreed with that saying much. Older doesn’t always mean wiser. Certainly doesn’t mean more moral,” he shoots back, keeping his eyes fixed firmly on the Master’s even as he gulps a little too hard, palms sweating against his crossed arms. 

“Apologize.”

“No.” 

“I /said/, APOLOGIZE!” The Master snarls, rubbing his hands together until the electricity between them no longer crackles in and out, instead keeping the charge constant and growing with every second. 

Steve does not run.

“I will never obey you, Master. And neither will he.” 

With a sharp laugh, throwing his head back, the Master shakes his head rapidly. “Oooooohoho, he’s ALWAYS obeyed me. And he always will!!! Always, always, always, ALWAYS!” And with the force of that last always, a near-shriek of madness, he aims directly at Steve’s chest and fires. 

Steve does not run.


	2. Chapter 2

**Notes for the Chapter:**

> TWO UPDATES IN A DAY! Told y'all I wasn't abandoning my baby. Hooray for sick inspiration!
> 
> (Re: self-harm tag. The Master punches things to feel pain because, like Pinocchio, he wants to be a real boy. It is left up to interpretation as to whether or not Koschei has any influence in making him do this as self-punishment.)
> 
> Enjoy!

He does not run, this time, because he does not have to. Despite the aim of the Master’s bolt, he changes direction at the last second and instead shoots near the window, immediately catching fire on the wallpaper. The Master stares at his hands traitorously, eyes darting between them like his shaking palms hold the answer, teeth gritted and his breathing ragged. Steve knows the answer, of course: /Koschei./ His Koschei, still inside, still fighting. His Koschei, protecting him even still when Koschei cannot protect himself. 

Keeping his eyes and body turned to the Master, Steve yanks the duvet off the bed and stumbles backwards, only looking away to smother the growing flames that had started to lick dangerously close to the ceiling. The fire alarm starts to blare, though, a loud, incessant whooping punctuated by the running of his teammates. They’re running to them, he realizes. They must’ve heard the blast, but they /can’t/ get in. They wouldn’t understand, and — Natasha and Sam especially — once the fighting instinct took over, Steve knows they wouldn’t hesitate to shoot the Master down. 

That can’t happen. Killing the Master means killing Koschei and that simply isn’t an option. He refuses to outlive this man. 

The Master tries to fire at him again, this time without warning, but the electricity no longer charges, instead fizzling out pathetically with barely a spark. He growls in frustration and tries again, and again, and again, but Steve pays him no mind. He barely gets to the door in time to lock it before Natasha can kick it open. “Don’t come in,” he yells, face almost pressed into the wood. “I’m handling it!” 

“Steve, what the fuck is going on?!” she shouts back, knocking almost frantically on the wood. The Black Widow never panics. Natasha, though…

“It’s Koschei, but it’s— it’s not /him/, I just—,” Steve glances back over his shoulder and the Master had fallen to his knees, angry tears streaking down his face as he punches the floor, the wood splintering around him. “I can’t explain it, but — trust me, okay?! I will let you guys in if I can’t handle it but I can, I know I can, I /can/!” 

“We’re all armed out here, buddy. We’re ready to go. You don’t have to do this alone,” Sam cuts in, his own heavier knock sounding a moment later. The very idea of them — his team, /their/ team — being armed against Koschei makes him nauseous. 

“It’s not like that, man. It’s not. Listen, just — just LISTEN to me. I need to handle this alone. He’s okay. He’s okay.” 

“Ten minutes,” he hears Clint drawl, calmer than the rest of them and Steve can practically see his bow and arrow aiming through the door. The others murmur their agreement and he knocks twice in acknowledgment before turning to the Master and dropping to his knees in front of him.   
He doesn’t speak.

“I need to kill you,” the Master grits out, no longer punching, but just staring at the wood chip piles around the holes he made, hands trembling violently and full of bloody splinters. How hard, Steve can’t help but think, must he have been punching to break skin? /His/ skin? 

“Why?” Steve asks calmly, automatically reaching out and brushing a wood chip off the Master’s shoulder. He doesn’t touch him anywhere else. 

“Why.” The Master echoes tonelessly before laughing a breathy, poor imitation of his earlier cackle, squeezing his eyes shut too-tightly and forcing more tears to drip through his lashes. Steve’s heart aches, just a little. “Because — /because/, you—you filthy, dirty ape, you —,”

“Stop.”

The Master stops, teeth still bared in anticipation of whatever he was going to say next. 

“/Why/ do you do this? Why do you need to kill me? No gimmick, no dramatics, just…tell me. Tell both of us.” 

Flicking idly at a wood chip like a child with a blade of grass, the Master suddenly looks so young and so lost that Steve thinks, just for a moment, he almost resembles Koschei after a nightmare. /It was like a lucid dream/. Koschei’s words float through his mind, spoken so long ago it seems like another lifetime. 

God, he must be so scared right now. 

“Real people kill,” the Master murmurs, so quiet and low that it takes a second for the words to process. Before Steve can say anything, he continues. “Real people kill, and maim, and /influence/ the world around them. When I hurt someone, I become a fact to them. Not…an illness, or a nightmare, or a /mistake/,” he glares at Steve accusatorially, “but a fact. A person. Real.” 

“Real people save lives too, you know,” Steve points out. The Master scoffs. 

“It is far easier to remember the ones who hurt.” 

The phrase “cool motive, still murder,” sounds in Steve’s head and he grimaces instead of replying. There’s a beat of silence before he says something. “That…can’t be it.” 

The Master lifts his hands and meets Steve’s eyes, flexing and curling his fingers. The splinters shift in the flesh at the movements, fresh blood seeping around them and dripping slow and syrupy down his hands. “I feel this. It hurts and I feel it. This body is /mine/ right now, and with it, I can feel pain.” He smiles suddenly, twisted with a desperate edge that seems like a plea. “Do you have /any/ idea how good it feels to feel pain when you’re not even allowed your own body?” 

“Now you know how he feels,” Steve responds, unable to keep the curtness from his tone. Part of him, admittedly, does feel for the Master, but — these excuses are that of a whiny child. Perhaps that’s all the Master is, really. A child throwing a temper tantrum. The Master’s smile falters and he looks away, clenching his hands into tight fists and Steve is struck with a startling clarity — self-harm. It’s /self-harm./

Which one of them is doing that?

“He should understand. Why doesn’t he understand? WHY DOESN’T HE UNDERSTAND?!” Someone knocks once at the door and the Master snaps his head up to glare at it sharply, his breathing ragged and his body tensed before he sags and relaxes, drawing his knees to his chest and embracing them. “If I didn’t share a body with Koschei, you would’ve let them kill me.” 

“Probably, yes. But you do.”

“So I live?”

“So you live.” 

“Mmm. That’s not living. This isn’t living.”

“If you didn’t use your time /in control/ to kill people, I might be a bit more inclined to find a way to separate you two,” he points out, crossing his legs instead of kneeling. The Master just rolls his eyes. 

“You sound like our ex,” he retorts, punctuating the “X” like a hiss. “Gonna throw us away too? Maybe I should kill you after all — saving Koschei the heartbreak surely counts as charity, hmm?” 

Steve doesn’t rise to the bait, instead grabbing one of the Master’s hand and starting to pick out the splinters. Surprisingly, the Master doesn’t fight him on it. “You /are/ supposed to protect him, you know.”

“Being a hero isn’t really my ‘thing,’ ‘case you haven’t noticed,” the Master mumbles, resting his chin on the crook of his elbow and watching. “I’m my own person — why should I exist only to protect someone else?”

“Because you’re /not/ your own person, Master.” 

He yanks his hand out of Steve’s grasp like a petulant child, going so far as to turn his body away from him to sulk. Rolling his eyes, Steve uses his superior strength to bodily lift the Master up a couple inches and turn him back around before taking his hand and resuming. The Master obviously wants to fight him, but he settles for glowering. Steve can handle glowering. “You need to give him back to me,” he says, trying to sound as informal as possible. “You’re a separate person, yes, but this was Koschei’s body first and after all the hell you put him through — you’re not entitled to take it over just because you want to.” 

“You don’t understand. You /can’t/, how COULD—,”

“I do. I understand, but it isn’t enough.” Steve’s hand tightens on the Master’s wrist, looking at him meaningfully. “He’s in there and he’s watching this and he needs to come out, Master. If you want to be — /real/, want to influence something /good/ for a change and prove that maybe, just maybe, we shouldn’t write off getting you a body completely, then give him back.” 

“…How do I know you’re not simply manipulating me?”

“You don’t. But Koschei’s stronger than you think and, if I know him as well as I know I do, his patience is wearing thin.” 

“You won’t hurt him.”

“I won’t have to.” 

They stare at each other, the Master’s hand still trapped in Steve’s grasp. For once, showing just the barest hints of, well, humanity, the Master accepts defeat. 

When the team kicks down the door precisely ten seconds after the ten minute mark, all they find is Steve holding Koschei, exhausted and shaken, in his lap as he picks the splinters from his hands.


End file.
